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.\" $Id: gelf_update_ehdr.3 3639 2018-10-14 14:07:02Z jkoshy $
.\"
.Dd August 27, 2006
.Dt GELF_UPDATE_EHDR 3
.Os
.Sh NAME
.Nm gelf_update_ehdr ,
.Nm gelf_update_phdr ,
.Nm gelf_update_shdr
.Nd update underlying ELF data structures
.Sh LIBRARY
.Lb libelf
.Sh SYNOPSIS
.In gelf.h
.Ft int
.Fn gelf_update_ehdr "Elf *elf" "GElf_Ehdr *ehdr"
.Ft int
.Fn gelf_update_phdr "Elf *elf" "int ndx" "GElf_Phdr *phdr"
.Ft int
.Fn gelf_update_shdr "Elf_Scn *scn" "GElf_Shdr *shdr"
.Sh DESCRIPTION
These functions are used to update ELF data structures on the underlying
ELF descriptor.
Class-dependent data structures in the underlying ELF descriptor
are updated using the data in the class-independent GElf descriptors
and the underlying ELF data structures are marked
.Dq dirty .
The conversion process signals an error if the values being copied
to the target ELF data structure would exceed representation
limits.
GElf descriptors are described in
.Xr gelf 3 .
.Pp
Function
.Fn gelf_update_ehdr
updates the ELF Executable Header with the values in the
class-independent executable header
.Ar ehdr .
.Pp
Function
.Fn gelf_update_phdr
updates the ELF Program Header structure at index
.Ar ndx
with the values in the class-independent program header
.Ar phdr .
.Pp
Function
.Fn gelf_update_shdr
updates the ELF Section Header structure associated with section
descriptor
.Ar scn
with the values in argument
.Ar shdr .
.Sh RETURN VALUES
These functions return a non-zero integer on success, or zero in case
of an error.
.Sh ERRORS
These functions may fail with the following errors:
.Bl -tag -width "[ELF_E_RESOURCE]"
.It Bq Er ELF_E_ARGUMENT
Arguments
.Ar elf ,
.Ar ehdr ,
.Ar phdr ,
.Ar scn ,
or
.Ar shdr
were NULL.
.It Bq Er ELF_E_ARGUMENT
Argument
.Ar elf
was not a descriptor for an ELF object.
.It Bq Er ELF_E_ARGUMENT
Argument
.Ar elf
had an unsupported ELF class.
.It Bq Er ELF_E_ARGUMENT
Argument
.Ar ndx
exceeded the number of entries in the program header table.
.It Bq Er ELF_E_ARGUMENT
Section descriptor
.Ar scn
was not associated with an ELF descriptor.
.It Bq Er ELF_E_MODE
ELF descriptor
.Ar elf
was not opened for writing or updating.
.It Bq Er ELF_E_RESOURCE
An out of memory condition was detected.
.El
.Sh SEE ALSO
.Xr elf 3 ,
.Xr elf_flagelf 3 ,
.Xr elf_flagphdr 3 ,
.Xr elf_flagshdr 3 ,
.Xr gelf 3 ,
.Xr gelf_getehdr 3 ,
.Xr gelf_getphdr 3 ,
.Xr gelf_getshdr 3
